Stool for molds for casting metal



c. H. ALDRICH M390 STOOL FOR MOLDS FOR CASTING METAL Filed pril 6, 1937 Patented Jan. 2, 1940 STOOL FOR MOLDS FOR CASTING METAL Charles H. Aldrich, Elizabeth, N. J., assigner to The American Metal Company, Limited, New York, N. Y., a corporation of New York Application April 6, 1937, Serial No. 135,218

1 Claim.

This invention relates to certain improvements in metal stools which are used as supports for molds for the casting of steel ingots or the like.

In a prior patent granted to me on May 5, 1936,

No. 2,039,872, I have described and claimed a stool for metal molds which comprises' a multiplicity of individual stool members, preferably of like shape, which are held Within a frame in such position as to form a metal platform upon which the casting mold rests. The individual sections are shown as grouped together and confined within a frame in such; manner that the stool presents on its upper surface a series of joints or crevices which permit expansion and contraction of the individual sections, the frame being provided with means for clamping or wedgng the sections in the frame. Preferably the construction is such that endwise expansion of the individual sections can freely take place.

The present invention provides a specific form of mold stool of this type, which is of minimum cost and weight, which is freely open to the surrounding air and easily assembled and disassembled. In the specic forms of device shown in the aforesaid patent, the individual sections of the mold stool are capable of reversal so that when their upper faces become pitted or roughened to an extent rendering them no longer available for use, the sections may be turned upside down within the frame and then reclamped to present a new supporting surface for the mold. The patent also instances a construction in which more than two faces of the individual sections can be utilized. According tothe present invention, the upper and lower faces of the individual sections can be used, but this may be very quickly accomplished by merely turning the stool over so that its top face becomes its bottom face, thus facilitating the re-use of the sections. The invention also includes other features oi' improvement which are more fully described hereinafter.

Referring to the drawing, which illustrates several forms of the invention- Figure l is a plan of a stool of considerable area intended to accommodate a mold of sizable proportions;

Fig. 2 is a side View of Fig. 1 looking from the bottom of the sheet upward;

Fig. 3 is a plan of a somewhat simpler, modified form;

Fig. 4 is an end view of Fig. 3 looking from right to left;

Fig. 5 is c. plan View of a still further modification in which the invention is shown in its ultimate simplicity;

Fig. 6 is an end view of Fig. 5;

Fig. 7 is a view taken on the line 'l-l of Fig. 5.

Referring first to Figs. 1 and 2, it will be seen that, as in my prior patent, I utilize a series of elongated and preferably rectangular sections A. These sections may be parallel-sided and may be easily obtained by modern methods of vertical casting. The number of sections A which are used in the-stool is dependent upon the size of the stool to be constructed, as is also their length, which, as shown in the drawing, is rfrom top to bottom. As a rule, the active portion of the stool upon which most of the mold rests Will be constructed of the sections A.

The assembled sections A are held together in the form of a stool by a series of bolts B, B, which are shown as three in number in the construction of Figs. 1 and 2, the number of bolts depending upon the dimensions of the stool. Each'` of the sections A is drilled transversely toprovide a passage for the bolts B. By tightening the Lbolts the sections are held together with great firmness, so that the assembled sections can be handled and utilized as one piece. It is desirable, particularly in molds of larger diameter, that each of the sections shall have the capacity of lateral expansion, and to this end my invention provides that each of the bolts shall be provided with a stiff helical spring C. The spring C may be arranged at either end, or both ends, of the stool, one end being ordinarily sufficient. In the construction of Figs. l and 2 the bolts are headed at their left-hand ends and provided with the spring C at their right-hand ends, the spring being located between the nuts D, D and shoulders E formed on an end piece F. The headed ends of the bolts engage shoulders G formed on an opposite end piece I-I.

The construction of Figs. l and 2 permits endwise expansion of the sections A by the simple expedient of making the bolt holes of somewhat larger diameter than the exterior diameter of the bolts. This method also permits any expansion which may take place between the top face of each of the sections and its bottom face.

It will be seen that the stool as a unit may be used with one of its surfaces uppermost until said surface is so pitted or destroyed that it becomes no longer feasible to continue it in use, Whereupon the stool may be merely reversed, Without disturbing the position of any of the sections, to bring the unused surface into operation. It will also be understood that a plane under-surface of the stool may rest upon the flat top surface of a mold buggy whereby to effectively distribute thereon the combined weight of the stool and mold.

In the construction of Figs. 1 and 2 the end pieces F and H are utilized not only to provide stii end sections, but also for several other purposes. One of these is to protect the bolt ends from injury, this being done by providing the end pieces with sockets J, J, so that the bolt ends are completely housed at each side of the stool. The sockets are of sufficient diameter to permit manipulation of the bolt heads and nuts by suitable wrenches. Another purpose of the end r pieces is to provide, on the top and bottom of the stool, preferably similar guides K, K, which afford a means for restraining a stool and mold against slipping when being carried upon a mold buggy, particularly when the latter is being moved with its load.

, The guides K, K, on whichever surface is being used as a top, extend upwardly and are adapted to engage the walls of the mold to locate the latter properly and to prevent it from slipping on the stool. They may be formed with inner cutaway portions L to better fit the exterior contour` of the mold. Suitably spaced depressions may be provided in the supporting surface of a buggy to receive the guides on the bottom of the stool whereby to restrict slipping between the stool and buggy.

In the construction shown in Figs. 3 and 4 the end pieces are omitted and, in order to protect the bolt ends, as well as make sure that the strains set up by tightening the bolts shall be distributed over a considerable area, cup-shaped members M, M are provided at one side of the mold which are of suflicient diameter to extend preferably across the entire depth of the sections A and which are deep enough to contain the screw-threaded bolt end, the springs, and the nuts. On the opposite ends of the bolts the bolt heads are housed in shallower cups N, N.

Figs. 5 to '7 represent the invention in its most simple and inexpensive form which, in View of a somewhat limited facility for expansion, is preferably employed only in stools of relatively small sizes where actual expansion would not be great. In these gures the bolt heads and nuts are engaged by plain washers O, O` of considerable thickness so as to distribute the strain across the sections A, and the springs C are omitted. In this simple form of the invention the irregularities in the contacting surfaces of the various sections A are relied upon to permit sufficient expansion and contraction to prevent warping of the sections. That is to say, to a certain extent the sides of the sections A meet with point-topoint contact of a multiplicity of small imperfections which may be flattened out by any expansion or may nest to a certain extent sufcient to prevent warping. The bolts B also assist somewhat in this process,.since a certain amount of expansion and contraction of these bolts takes place due to the heating of the stools by the mold and their subsequent cooling between casts, with the consequent heating and cooling of the bolts.

In all of the constructions I prefer to employ sockets or recesses P, P on opposite sides of the stool which may be grasped by the crane or other hooks to move the stool from place to place and toy reverse it.

It will be seen that in all the constructions I provide a very cheap and simple form of stool which can be readily reversed in its position to bring a new bottom casting face to the mold without the necessity of adjusting individual sections. 'Ihe invention alsov avoids the necessity of using a frame for the purpose of maintaining the sections in proper assembly. At the same time each of the sections is capable of being removed and replaced, or reversed, when this may be necessary to maintain the casting surface of the stool in proper condition.

Stools, according to the present invention, are mainly applicable to the casting of Various metals by the use of cast iron molds, although they may be otherwise employed if desired. The sections A of the stool, as in my said previous patent, are preferably constructed of copper or some alloy which provides ready heat transference. Substantial portions of the said sections are open to atmosphere and, adequate heat dispersal may, hence, take place by conduction and convection.

What I claim is:

A stool for molds for casting metals or the like comprising a series of individual sections comprising elongated flat sections assembled with their at sides abutting and with their top and bottom faces in iiush relation, said sections having holes passing from side to side thereof, and tension members extending through said holes to fasten said sections together in a unitary platform structure, said sections having similar top and bottom faces to provide a stool which can be used in reversed position without removing any of the sections. l

CHARLES H. ALDRICH. 

